JPS59617A - Multi-pen recorder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to multi-pen recorders, and more particularly to a new and improved inking device for single gravity feed capillary type multi-pen recorders.

Various pressurized inking devices have been proposed in the past in which ink is constantly pressurized to a large number of recording pens, but these devices have had drawbacks. That is, the ink nib must be pressed against the chart paper with considerable force to prevent leakage from the nib due to pressure acting on the ink supply. This increases the friction between the nib and the chart paper, which not only shortens the life of the nib, but also slows down the response time of the pen and increases the overall hysteresis of the device.

The higher drive power required to obtain good response times also requires a more powerful pen servo motor and appropriate feedback devices.

As a result of these drawbacks, many current multi-pen recorders are of the gravity-fed capillary type and use a separate ink bottle for each pen. However, in these gravity-fed multi-pen systems, some form of priming mechanism is used to set the initial flow of ink to each nib and to force the ink through the drawer tube if it becomes clogged. Required for each ink supply. Traditionally, rubber balls.

A piston and cylinder, or bellows type device has been used on the cap of each ink bottle in a multi-pen gravity feed capillary type recording system. In these devices, an ink bottle was pressed and the ink entered a rubber bulb or pump, which then tended to flow onto the user's hands. Also, when the pump was placed on an ink bottle cap, the relatively small dimensions of these ink bottle caps left little room for a large ink tube. Therefore, relatively small diameter flexible tubes are usually used to connect the ink bottle cap and the pen mounted on the servo motor, and the length of these tubes is typically 15 to 20 cr.
It's IT.

These flexible tubes are typically made from plastic materials that are easily permeable to the solvents in the ink solution.

With such lengths of thin-walled, small diameter tubing, the dye in the ink can precipitate and clog the tube after several weeks of non-use of the inking device.

Examples of various types of prior art inking devices for recorders are shown in the following US patents: US Pat. Sunaichi, Han
d Patent No. L8119.0811, Bowditch
Patent No. 2.727,802; Cannon Patent No. 2
．． 800. U85; Holloway Patent No. 2,82
No. 0,19; Dressel Patent No. 2.821,91
No. 9: Summers, Jr., et al. Patent No. 5,
01j6.556; Winston Patent No. 5,06
0. l+29; G11L, Jr-, et al. Patent No. 5.1
No. 85,991; 5ihvonen Patent No. 3.21+
No. 7.519; Behmoras et al. Patent No. 299
．． No. 1+56; Hartai Patent No. 5. U55,11
No. 211: Schweit, zer Patent No. 3.511
1.8F, No. 0; 5 anderson et al. Patent No. 5
,571. U50i Abr-ams et al. Patent No. 5,
No. 6114.91IO: 5kafvenst, edt.
et al. Patent No. 1I, 053,901; Brown+Jr.
, Relssue Patent No. 25.692, the following patents are also cited as having general relevance to the present invention. That is, Carter Patent No. 626.750:
England Patent No. L907,76; Mil
ler Patent No. 2,769,575: Marwell
Patent No. 5.201! , No. 659; Kirch Patent No. 5.1 No. 18.0511.

It is therefore an object of the invention that one or more of the disadvantages of the prior art devices mentioned above are obviated.

It is an object of the present invention to provide a new and improved ink priming device for a gravity-fed capillary type multi-pen recorder.

Another object of the invention is that a reservoir mechanism is provided for selectively supplying pressurized gas to any one of the reservoirs associated with each recording pen of the recorder. A new and improved ink priming device for multi-pen recorders is provided.

It is another object of the present invention to provide a common manifold for recording pens supplied with pressurized gas and for selectively supplying gas from the manifold to an ink bottle associated with a particular recording pen to prime the pen. It is an object of the present invention to provide a new and improved ink priming device for a multi-pen recorder, in which each individual control pulp is provided.

Another object of the invention is that an ink comprising a dye in a suitable solvent is connected to a movable recording pen element via a flexible tube member, the flexible tube portion being permeable to the ink and connected to the recording pen. A novel improvement in a spout for use in recorders, having a length such that the concentration of dye in the ink at its end does not exceed its saturation value.

An object of the present invention is to provide an inking device that is free from clogging.

Another object of the invention is that a flexible tube is used to connect the ink supply and the recording pen, said tube being short enough that the evaporation of the ink solvent through the tube wall prevents the transfer of dye to the ink supply. Novel improvements in sump for use in heavy recorder analogues, which provide a non-clog inking device, where diffusion occurs so that the concentration of dye in the ink at the end of the tube near the recording pen does not exceed the saturation value. It is to provide.

SUMMARY OF THE INVENTION The present invention relates to an ink priming device for a gravity-fed capillary type multi-pen recorder in which a separate ink bottle is provided for each recording pen. A gas manifold common to all of the ink bottles is connected to each ink bottle via a suitable control pulp, so that the gas pressurized into the manifold is selectively applied to any ink bottle and removes the ink from that bottle. extrude to prime the corresponding pen.

When the recording pen is primed and the control pulp is released, the gas pressure is bled off.

The fruiting device then operates as a conventional gravity-fed capillary recording device. Therefore, during regular use of the recording pen, the ink is not pressurized, and therefore, compared to normal pressurized inking devices, the pen tip is pressed relatively lightly against the char 1/paper and the pen motor is operated with relatively low force. can be driven by

In accordance with another aspect of the invention, a clog-free inking system is provided for each recording pen by utilizing short lengths of flexible thin-walled tubing to supply ink to the movable recording pen elements.

The length of this permeable thin-walled tubing is short enough.

Evaporation of the ink solution through the walls of the tubing is accompanied by diffusion of the dye into the ink bottle, so that the concentration of dye in the ink at the end of the tubing connected to the recording pen does not exceed the saturation value. As a result, the recording pen can remain stationary for long periods of time without dye deposition and clogging of the tubing or recording pen.

These and other objects and advantages of the invention will be better understood by reference to the following detailed description and accompanying drawings.

Referring now to the drawings, the ink priming system of the present invention is illustrated, and one channel of the multi-pen recorder system is shown in detail. More specifically, it includes a capillary pen element 10fi consisting of a metal tube with a closely spaced through hole of small diameter, and a nib portion 12 adapted to engage chart paper. penniremen) l Oi
d Mounted within a lightweight metal frame Ill, frame l
11 is a suitable galvanometer type pen motor (not shown)
is fixed to.

The element 10 rotates the shaft 15 in accordance with a predetermined input signal.
It can be closed and rotated. Each channel of the multi-pen recorder is provided with an ink bottle 16, and the ink 18 in the bottle 16 is transferred to a metal tube 20 mounted in a camp portion 22, a thick-walled tubing section 211° of relatively large diameter and a small The recording pen element 1 is connected to the recording pen element 1 via a thin-walled tubing section 26 of
0 at all times.

During normal operation of the recording channel, ink 1 in the bottle 16
The space above 8 is not pressurized, so this recording system acts as a normal gravity fill capillary system. However, in accordance with the present invention, a pressurized ink priming scheme is provided for each channel of the multi-pen recorder. Let me elaborate further.

A suitable gas, such as carbon dioxide, is stored in liquid form within a relatively large disposable bottle 2, and the liquid carbon dioxide within the bottle 2 is at a relatively high pressure, such as 8115 psig. A bottle holding and punching device 311 is used to hold the bottle 2 and direct the carbon dioxide into the tube 36. A pressure regulator 112 is supplied via manifold valve 38 and line IIO, which pressure regulator
Reduce the pressure of carbon dioxide from lI to l0T) to a pressure within the range of 81 g. Although other hydrocarbons or halo carbons can be utilized with lower vapor pressures and use weaker vessels and simple pressure regulators 112 than when carbon dioxide is used, carbon dioxide is preferable from a fire and environmental standpoint.

A spare carbon dioxide bottle ll11 is attached to the bottle holding and punching device itt6 and can be selectively used in place of the bottle 32 by appropriately actuating the manifold pulp 38.

Gas exiting regulator I12 is supplied via three-way valve I+8 to gas manifold 50, which is common to all of the recording channels of the multi-pen recorder. More specifically, the manifold 50 has a central chamber 2 that extends longitudinally of the manifold 50 and is connected to the pulp 8 via a conduit 511. A series of control valves 56 are mounted on the top wall of the manifold 500.

They each communicate with chambers 52 via vertical bores 5g. Each control valve is actuated by a depressable top member 60. The flexible tube 62 is
A metal sleeve 611 attached to the cap 6'0 and a metal sleeve 66 attached to the ink bottle cap portion 22 are connected, and the sleeve 66 connects to the space inside the ink bottle 16 via a conduit 68 formed in the cap 22. It communicates with 50. The cap portion 22 includes an outwardly projecting flange portion 70 that engages the top wall thereof within the outer cap member 70, with a sealing washer 714 provided on the flange 70 and a washer 71I attached to the inner cap member. 22 is sealed to the upper end of the zero thread portion of the ink bottle 16, and a pressure ring is provided between the bottle 16 and the cap member 22.

In detail, the Tsukini control valve 56 has a so-called tank valve structure and is similar to a typical automobile tire valve.

That is, the pulp 56 has an external oozing 76,
Its bottom end is threaded into the bore 58 and has a nozzle γ
A washer 78 and a seal ring 80 are provided to maintain a tight seal between 6 and manifold 50. A two-piece valve core 82 is threaded into the upper end of the housing 76 to form a tight seal between the pulp core seal 811 and the housing 76. Pulp core pin 86d is slidably mounted within valve core 82 and carries a valve root seal 88 which is permanently PC biased upwardly by coil spring 90 into engagement with the bottom end of valve core 82. The depressable cap member 60 has a downwardly projecting pin 92 in its top wall so that when the cap 60 is depressed, the valve core bin 86 snaps into the bin 9.
2 and is pushed down to open the control valve 56. When the cap 60 is pressed down, the cap 60
A sealing member 94 mounted therein moves downwardly into engagement with the upper end of the housing 76 to prevent gases supplied to the manifold 52 from escaping to the atmosphere. Thus, when camp 60 is depressed, pressurized carbon dioxide within manifold 52 is supplied to space 50 at the top of ink bolt 16 via pulp 56 and tubing 62.

As a result.

Ink 18 is forced through tubes 20, 211, 26 and into recording pen element 10, thereby priming recording nib 12.

Gap 60 is depressed by the operator for a sufficient amount of time to establish the desired capillary ink flow between bottle 16 and nib 12, after which cap 60 is released. Always,
The cap 60 is positioned by a spring 90 and the sealing member 9+1 is spaced above the upper end of the housing 76.

When the cap 60 is released after an ink priming operation, the pressure established within the space 0 of the ink bottle 16 and the spring 90 work together to force the cap 60 upwardly so that the pressurized carbon dioxide within the space 50 is forced into the housing. It bleeds through the space between the outer thread 96 at the upper end of 76 and the inner end of cap 60 .

A threaded insert 98 is secured to the bottom end of the cap 60 to hold the cap 60 loosely over the top end of the pulp 56. First, in order to assemble the cap 60 onto the upper end of the pulp 56, the insert 98 is threaded into threaded engagement with the externally threaded portion 96 of the housing 76 so that the cap 60 is assembled onto the upper end of the pulp 56. held loosely. The tubing 62 is then connected to the corresponding ink bottle 16.

Manifold 5 during the period when the recorder pen is not primed
To prevent leakage of carbon dioxide from the 0, the control pulp 56 is preferably made of
5 chrader Div, of Co., Ltd., in tank pulp form, which has a leakage rate of less than 1 nanoliter per second. Since the remainder of the ink priming device is only intermittently pressurized, the corresponding seals do not need to have such low leakage rates.

The operation of the ink priming device of the present invention will now be described. During periods when the ink priming device is not required, the three-way pulp 118 is moved to a position where gas release from the regulator II2 is inhibited, thereby causing the flow of gas into the manifold Champara 2. Cut off the supply of pressurized carbon dioxide. This minimizes the chance that one of the control pulps 56 will accidentally leak and release all of the carbon dioxide in the bottle bottle 2 to the atmosphere. However, when the ink priming device is to be used, the three-way pulp qg is turned in a position where the discharge gas from the regulator +12 is supplied via conduit 54 to the manifold champer 2. When the operator desires to prime a particular one of the recording pens IO, he depresses the corresponding one of the caps 60, thereby opening the associated control pulp 56 and supplying pressurized carbon dioxide to the ink bottle 16. , the flow of ink is established to the seven pen nibs 12 via the above-mentioned passages.

As will be appreciated in this regard, conduit 511
can be made relatively long so that the carbon dioxide bottle 52.1111.degree. pressure regulator 112 and pulp 513.118 are located far away and the manifold 50 is located relatively close to the row of ink bottles.

Preferably, conduit 511 is made from other plastic material. In accordance with another aspect of the invention, in addition to the control pulp required for each ink bottle 16 associated with each recording pen of a multi-pen recorder, the manifold 50 also includes one side or two auxiliary control pulps 5. It is equipped with

These auxiliary control valves are used to squirt ink from any one or each of the recording pens 10. More specifically, the auxiliary control valve is connected to a bottle 16 filled with a suitable solvent rather than ink 18. Outflow pipe 21+a connected to a bottle of solvent
(Fig. 8g3) is then connected to the elbow block 100. This elbow block may be of the type illustrated and described in U.S. Patent Application No. 867.201, filed January 5, 1978. elbow block 10
0 has a vertical through-opening 102 in its top wall into which the nib 12 is tightly inserted. The opening 102 is the conduit 10
It is connected to the pipe 211a via the metal pipe 106 protruding from the block 100. Auxiliary pulp 56a
is forced into the end of the nib 12 through the conduits 104.102 of the block 100, so that the solvent is injected into the recording pen lO and its associated tubing (26.21).
is sent in the reverse direction through the elements, thereby cleaning these elements and removing precipitated dyes etc. remaining inside. As will be appreciated in this regard, when such cleaning operations are performed, the ink bottle 16 is removed from the associated recording pen 10. Alternatively, auxiliary valve 5
The bottle associated with one of 6a may contain air;
In that case, the two inks are ejected from the selected one of the recording pens 10 by placing the nib 12 within the opening 102 and opening the corresponding auxiliary control valve 56a. When valve 56a is opened, pressurized carbon dioxide is forced into the air bottle, so that pressurized air is applied to nib 12 and forces ink back through recording pen IO and tube 26.2+1. Such flushing or flow of air into the recording pen is utilized, for example, to prepare the recorder for storage.

is provided, which is used to pressurize the manifold Champara 2 during periods when the carbon dioxide bottle 2 is not in use. To explain in more detail, there are check valves 111 on both ends of the pump 110fi! , 11g. Check valve 1111 is connected to one end of long pipe 116, and the other end is connected to three-way valve 4g. In the third position of valve 118 tube 1161-11
．． It is connected to a pipe 511 communicating with the manifold Champara 2. Approximately 10 psig when rubber bulb 112 is squeezed
Air pressure at '1 is set in the manifold chamber and check valve 1111 prevents escape. After proper pressure is set in manifold Champara 2.

Any one of the control valves 56 is opened by depressing the cap 60 and pressurized air is supplied to the space above the ink 18 so that the corresponding pen is primed as described above.

In accordance with another aspect of the invention, hand pump 110 includes tube 11
A check valve 11g at the other end of the rubber bulb 112 is connected to the tube 116. When the ball 112 is squeezed and released.

Manifold chamber 52 as squeeze bulb 112 expands.
A vacuum is set inside. In such a configuration approximately -1,5
A vacuum of p s i g is set. After this level of vacuum is established within the manifold chamber 52, depressing any one of the caps 60 opens the corresponding control pulp 56.

The vacuum in the manifold chamber 2 is thereby used to draw ink from the corresponding recording pen IO into the ink bottle 16. Such an arrangement would be used in place of the elbow block arrangement described above to remove ink from the recording pen 10.

In accordance with another important aspect of the invention, the tubing 211 whose upper end is joined to the right-angled end portion 120 of the tube 20 has a relatively large inner diameter and a relatively thick wall so that the solvent present in the ink 18 can be removed. cannot easily evaporate through the walls of tubing 211. Tubing 21j is preferably made from polyvinyl chloride or ethylene vinyl acetate, 0.062 inches (1.6 wm
) and an outer diameter of 0.125 inches (3.2 wm ) and may have an inner lining of polyethylene to reduce evaporation. The tubing section 26 has a relatively small inner diameter so that it can fit over the capillary end portion 28 of the recording pen IO, and is sufficiently flexible so as not to restrict movement of the recording pen during recording operations.

Preferably, the tubing section 26 is also made from polyvinyl chloride and has a diameter of 0.025 inches.
It has an inner diameter of O, OI + 6 inches (1.2 inches) and an outer diameter of O, OI + 6 inches (1.2 inches).

In prior art configurations, tubing section 2
A tube of size 6 is connected from the ink bottle 16 to the recording pen 1.
0 end portion 28, the distance being 15-20 crn in some cases. Such small diameter tubing was used in prior art configurations when rubber bulbs were used on ink bottle caps to prime recording pens. The inventors have discovered that when such a long, small diameter tubing 26 is used, ink can flow through the relatively thin, permeable wall of the tubing when the recorder is not in use and the nib 12 is not moving. Substantial evaporation of the solvent occurs. Since the evaporated solvent had to be replaced by drawing ink from the ink bottle, a relatively large ink flow was set up that moved at a low rate per day, and this ink flow exited the ink bottle and traveled along the tubing. Transferred to replace evaporated solvent. Thus, as additional ink is drawn from the ink bottle, the concentration of dye in the small diameter tubing increases until it reaches a saturation value, at which point some of the dye cannot diffuse back into the ink bottle.

The dye will precipitate and clog the tubing. However, one inventor has determined that the dye is only about 1 sm per day.
We found that scales diffused from such small-diameter tubing at a rate of . This means that after a short period of inking equipment disuse, the dye precipitates out above the saturation value and 15-20 c.
Means to clog tubing with a length of rn.

In accordance with the present invention, tubing section 26 has a length such that evaporation of ink solvent through the walls of section 26 is substantially balanced by diffusion of dye into the spinning end of tubing section 21. As previously mentioned,
Because tubing 2++ has a relatively large inner diameter and there is relatively little evaporation through its thick walls, the concentration of dye in the ink adjacent tubing 26 is substantially the same as in bottle 16. Thus, large diameter tubing 21
1, the ink bottle is effectively attached to the end of the short tubing section 26, thereby
The dye is diffused over a short length of tubing 26 to maintain the ink below saturation over the entire length of tubing 26.

Assuming that the evaporation of the ink solvent is uniform along the length of the tubing section 26, and if the density of the dye divided by the saturated density is expressed as "rho", then the idealization shown in FIG. Characteristic 120 may be calculated for a steady state or equilibrium condition where the dye concentration is saturated at the end of tubing 26 adjacent recording pen section 28. That is, ρfol=1.0. In Figure 4, the value “ρ
(y)· is plotted on the vertical axis, y is plotted on the horizontal axis, and y = ([7rth·X. In this equation, X is the distance from the pen end of the tubing 26, and D is the ink The amount L/V for a particular tubing is the diffusion coefficient of a particular dye molecule used in the tubing. determined by measuring the time, i.e., the length of the tubing divided by the rate at which the ink must enter the tubing and fill it. In the case of tubing, it takes a period of 15-20 days for all of the water to evaporate from a 2ocrIT length of tubing.

Idealized properties 120 are specific to specific tubing and ink 1
can be used to determine the appropriate length of tubing 26 for the concentration of dye in 8. Preferably, the dye in the ink lε in the bottle 16 is 50% of its saturated blackness.
, and thus the concentration can be increased substantially until saturation is reached. If the ink 18 has a higher concentration in the bottle 16, the trace will be less black.

The concentration change becomes small before reaching saturation. On the other hand.

If a density lower than 50% is used, the trace becomes progressively brighter as the density is reduced. Fourth
The concentration of 0.5 (50%) from characteristic 120 in the figure is 1.17
Gives a y value of 711. The allowable length of the tubing 26 under ideal conditions of characteristic 120 is given by the formula x=f ding ding wa ■
・Can be calculated from 1.17711. On the other hand, if the amount of dye in the ink in bottle 16 is 20% (02), the length of tubing 26 will be substantially larger, corresponding to a y value of 1.8 in FIG. . As mentioned above, the value L
/V is obtained by measuring the time required for all of the water to evaporate from a given length of tubing through its walls. Characteristic 120 in FIG. 4 is based on ideal conditions and corresponds to the condition that there is an equilibrium dye concentration distribution and that the concentration of dye at the pen end of tubing 26 never exceeds an equilibrium value of 1.0. It should be emphasized that Since it is not necessary for the inking device to play a role with such strict requirements, the length of the tubing 26 actually used may be somewhat longer than that indicated by characteristic 120, and even more unused The tubing 26 will not become clogged during this period. For example, polyvinyl chloride tubing 2 with the dimensions described above.
6, the tubing 26 is 125 inches (52
M).

The ends of the tubing 26 are attached to the larger tubing 214 using a suitable adhesive, such as PVC dissolved in cyclohexanone or cyclohexane or other suitable adhesive of the type used for PVC sanitary fittings.
conveniently secured within the edge of the. In this regard, it is pointed out that the preferred arrangement for supplying ink from reservoir 18 to capillary end portion 28 would be a conduit having a gradually tapered internal cross-section. however.

Such a tapered tube is extremely difficult to manufacture economically.

Alternatively, one could approximate a tapered tube by using several lengths of tubing with progressively increasing inner diameters and providing a stepped conduit with progressively increasing inner diameters in the direction away from the pen portion 28. It will be done.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the inking device of the present invention. FIG. 2 is a sectional view taken along line 2 in FIG. 1, showing the tubing connections of an ink bottle and a recording pen for one channel of a multi-channel recorder system. Figure 1 is a cross-sectional view of an attachment that may be used with the apparatus of Figure 1; FIG. 4 is a graph useful in illustrating the non-clogging feature of the present invention. 10--pen element, 12-one nib, 1)↓--
Metal frame, 16--ink bottle, 1g=-ink, 20--metal tube, 22--cap,
211.26--Tubing. 28-pen end part, u〇--space, u2--C
O, bottle, U4-1 holding device, U6--tube,
5g--manifold pulp, qo--tubing,
112-One Pressure Regulator, 1I11-One Child Bei CO
2 bottles, l18-1 three-way pulp. 50--cass manifold, 52--center chamber, 54--conduit + 56--control pulp, 58--bore, 60--cap, 62--flexible tube, 611.66--metal sleeve, 70 --Flange, 72-1 cap
7 +1--Seal washer, 7-low housing, 7g-1 washer, 80--Seal ring,
82--Pulp core, 8Il--Seal, 86
--Pulp core pin, 88--Valve seat seal,
90--Coil spring, 92--Bin, 94
--Sealing member, 96--Threaded part, 98-
1 insert, 100-elbow block, 102
-Ikkairo, 1011--Conduit, 106--Metal pipe,
110--71 hand pump, 112--rubber bulb, 1111.118-1 check valve,
116--Long tube.

Claims (1)

[Scope of Claims] 1. A mechanism including a plurality of recording pens and a plurality of separate ink reservoirs, one for each pen, for constantly supplying ink to the pens by a gravity-fed capillary system; and the recording pens. a common gas manifold, a mechanism for supplying pressurized gas to said manifold, and a pulp mechanism for individually connecting said ink reservoirs to said manifold to selectively prime any one of said recording pens. A multi-pen recorder equipped with 2. A mechanism comprising a plurality of recording pens and a plurality of separate ink reservoirs, one for each pen, for constantly supplying ink to said pens by means of a single gravity feed capillary system, and a pressurized gas supplied to any of said ink reservoirs. and a mechanism for selectively priming a selected one of said recording pens. 5. Claim 1, wherein the gas is carbon dioxide
The multi-pen recorder according to item 1 or 2. 4. Claims in which the gas supply mechanism includes a container filled with liquefied gas at a relatively high pressure, and a mechanism connected to the container for reducing the pressure of the gas supplied to the manifold. The multi-pen recorder described in item 1. 5. The pressure of the gas is reduced to 4 to 10 by the pressure reduction mechanism.
5. The multi-pen recorder of claim 4, wherein the multi-pen recorder is reduced to psi (approximately 0.2 s to o, rKy/d). 6 Hand pump and the pressure reduction mechanism or...
5. The multi-pen recorder of claim 4, including a second pulp mechanism for selectively connecting the output of a hand pump to the manifold. 7. The multi-pen recorder according to claim 6, wherein said hand pump comprises a squeezeable sphere and check pulp for supplying pressurized air to said manifold. g a mechanism for reducing the pressure within said manifold below atmospheric pressure, such that ink within any one of said recording pens may be selectively drawn back into a corresponding ink reservoir by selective actuation of said pulp mechanism; The multi-pen recorder according to claim 1. 9. The multi-pen recorder according to claim 1, including a stop mechanism for separating the gas supply mechanism from the manifold during periods when priming of the recording pens is not required. a mechanism including a plurality of recording pens, a plurality of separate ink reservoirs, one for each pen, for constantly supplying ink to the pens by gravity-fed capillary system; a manifold common to the recording pens; A mechanism including a plurality of valves, one for each pen, for individually connecting reservoirs to the manifold, and a reservoir mechanism for reducing pressure within the manifold below atmospheric pressure. This allows ink in any one of the recording pens to be selectively drawn back into a corresponding reservoir by selective actuation of the pulp mechanism. Multi-pen recorder.